Softpedia quoted the unnamed developer, who argued that the fixes coming in 10.8.1 not only “resolve all the reported battery drainage issues” that came with the release of 10.8, but that the improvement in battery life is “quite substantial.”

Not long after the release of Mountain Lion late last month, user reports began rolling in suggesting that the new OS was draining the batteries on their MacBook Pro and MacBook Air faster than Lion (10.7) did. Some Retina MacBook Pro owners were reporting losing as much as 3+ hours of battery life under Mountain Lion when compared to Lion.

According to Softpedia’s source, that difference in battery life is reversed in 10.8.1. “Until I installed 10.8.1, my MacBook was showing 4h:05m after a full charge,” the developer claimed. “After installing 10.8.1 it’s showing over 8h.”

Apple has been seeding developer betas of 10.8.1 for just over a week. The company has not yet announced when it plans to release 10.8.1 to the public.